A sequence of very stable and plain beeps from the monotron. Processed by a virtual signal chain.

The headphones output from the monotron was fed into the mic input on my laptop soundcard. The sound was frequency split with the lower frequencies triggering a Tracker (free VST effect from mda @ smartelectronix, tuned as a suboscillator).

I think for this one also the higher frequencies were fed to Saro (a free VST amp sim by antti @ smartelectronix).